Milling Machine

out of te box
i don't know where i need to place me question

i'm repacing an old hydrolic milling machine sinsinnati cim-x with electronic controle
displacement about x1300 y700 z700
tool power 3f 7.5kw gearbox 16 speeds
the servo motor for xyz 3.8kw 2500rpm B2 serie shenzhen xinlichuan electric co. ltd (china)
for a and b only 1kw 1000rpm same brand

2 years ago i make a small setup with 12ncm steppermotor and that work nicely
now i take the same setup and change only setting in the .ini file
i have a leadsaxe of 1/2"/rotation a first reduction on the machine 3/2 and afther that i place a timingbelt by meself 64/22 all this had a result of 2.9104 mm/rotation of the servomotor
i have 10000 puls/rotation --> 3435.9 puls/mm
it seams like its way to much for for the output of the step generator
i reduce already the stepdir dirhold steplen stepspace to a min of 1350 when i go lower the driver don't respond
"""""""""""do i need this high precision of 3.4 puls / micron ?""""""""
what is acseptable 2 puls / micron or is 1 puls already ok
i found out for x axe i have a backllach off 0.03mm
i like a rapide speed of 6m/ninute
i can change the pulsrate in the driver to a lower value

a second problem i face and thats why i like to get a second mesa card
for testing is this machine realy dangerous its go fast and its very powerfull

i like to setup again the little test simulation to try and error there

in the ini file you can do the setup for homing
now the homing go in the wrong direction
and till now i don't find how to set the exsact value at home position like +650.for the x axe so that the center of the turntable is exsackt 0

can i found somewhere a explanation how i have to change the values of the axes in the .ini file and what is the effect of the changing

when i start a complete niew setup i got an error linuc cnc cant comunicate with the messa board

First, you should start a new thread, and not add this to an unrelated thread.

At 1350 ns step time and step space you would be limited to about a
270 KHz step rate (leaving a 25% margin for headroom), this would limit
your maximum velocity to 270000/3436 mm/s or about 80 mm/sec

This is limited by your drives minimum step pulse widths, so the only way to
increase velocity is to lower the drives step/turn number.

As to the other questions, you would need to provide more information
on your machine and hardware setup to allow forum readers to help.

is it posible to get a presision of 0.001mm  on such an old machine and how many pulses/micron do i need for this precision 
is 1 puls/micron enough  or do i need  2 pulses  or more ?

how do i change the value  to get a  homing at a value of  -600  and afther homing the axe stay ther  
at the moment when i run a homing  that work  i see the value for the x-axe set at -600 but the axe is runnig to o  alt low speed homing speed
can you make a setting so you have a higher speed  going to home  and 5mm before homing go to low speed for do the homing using 2 homeswitches 

#******************************************
[AXIS_X]
MAX_VELOCITY = 100.0
MAX_ACCELERATION = 250.0
MIN_LIMIT = -601
MAX_LIMIT = 600
[JOINT_0]
TYPE = LINEAR
HOME = -600
FERROR = 10.0
MIN_FERROR = 1.0
MAX_VELOCITY = 100.0
MAX_ACCELERATION = 750.0
# The values below should be 25% larger than MAX_VELOCITY and MAX_ACCELERATION
# If using BACKLASH compensation STEPGEN_MAXACCEL should be 100% larger.
STEPGEN_MAXVEL = 200.00
STEPGEN_MAXACCEL = 1500.00
P = 1000.0
I = 0.0
D = 0.0
FF0 = 0.0
FF1 = 1.0
FF2 = 0.0
BIAS = 0.0
DEADBAND = 0.0
MAX_OUTPUT = 0.0
# these are in nanoseconds
DIRSETUP   = 2000
DIRHOLD    = 2000
STEPLEN    = 2000
STEPSPACE  = 2000
STEP_SCALE = 3435.9343
BACKLASH = 0.04
MIN_LIMIT = -601
MAX_LIMIT = 600.0
HOME_OFFSET = -600.000000
HOME_SEARCH_VEL = -1.000000
HOME_LATCH_VEL = -0.500000
HOME_FINAL_VEL = 0.333333
HOME_USE_INDEX = NO
HOME_SEQUENCE = 1
#*************************

Did you study homing setup documentation:
linuxcnc.org/docs/html/config/ini-homing.html

I don't think there is an easy way to to slow the homing motion
before the home switch is hit, but I would think you could increase the
home search velocity to more than 1 mm/s and the home final velocity
much faster.

For example with a home search velocity of 25 mm/s, and using
your velocity and acceleration numbers or 100 mm/s and 250 mm/s^2,
the home switch overrun would be only 1.25mm

(overrun = stopping distance = V^2/2A)